Change in coreboot[master]: mainboard/google/soraka: Tune I2C params (hcnt, lcnt, hold time)

[Furquan Shaikh (Code Review)]

Furquan Shaikh has uploaded this change for review. ( https://review.coreboot.org/21242

Change subject: mainboard/google/soraka: Tune I2C params (hcnt, lcnt, hold time)
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mainboard/google/soraka: Tune I2C params (hcnt, lcnt, hold time)

Tune I2C params for I2C buses 0, 1, 2, 4 and 5 to ensure that the
frequency does not exceed 400KHz.

BUG=b:35948024
TEST=Verified for 25 iterations that the frequency on each bus ranges
<= 400KHz.

I2C0: 393 - 397
I2C1: 393 - 400
I2C2: 392 - 400
I2C4: 392 - 400
I2C5: 392 - 400

Change-Id: I3e12c75eb7e82a83aa6a6bcfcc11c12f83f2d3d4
Signed-off-by: Furquan Shaikh 
---
M src/mainboard/google/poppy/variants/soraka/devicetree.cb
1 file changed, 65 insertions(+), 12 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/42/21242/1

diff --git a/src/mainboard/google/poppy/variants/soraka/devicetree.cb b/src/mainboard/google/poppy/variants/soraka/devicetree.cb
index 88c7c7d..3366f26 100644
--- a/src/mainboard/google/poppy/variants/soraka/devicetree.cb
+++ b/src/mainboard/google/poppy/variants/soraka/devicetree.cb
@@ -165,23 +165,76 @@
    register "usb3_ports[2]" = "USB3_PORT_DEFAULT(OC_SKIP)"	# Type-A Port
    register "usb3_ports[3]" = "USB3_PORT_EMPTY"		# Empty

-	register "i2c_voltage[0]" = "I2C_VOLTAGE_3V3"		# Touchscreen
-	register "i2c_voltage[1]" = "I2C_VOLTAGE_3V3"		# H1
-	register "i2c_voltage[2]" = "I2C_VOLTAGE_1V8"		# Camera
-	register "i2c_voltage[3]" = "I2C_VOLTAGE_1V8"		# Pen
-	register "i2c_voltage[4]" = "I2C_VOLTAGE_1V8"		# Camera
-	register "i2c_voltage[5]" = "I2C_VOLTAGE_1V8"		# Audio
+	# Touchscreen
+	register "i2c_voltage[0]" = "I2C_VOLTAGE_3V3"
+	register "i2c[0]" = "{
+		.speed = I2C_SPEED_FAST,
+		.speed_config[0] = {
+			.speed = I2C_SPEED_FAST,
+			.scl_lcnt = 180,
+			.scl_hcnt = 85,
+			.sda_hold = 36,
+		},
+	}"
+
+	# H1
+	register "i2c_voltage[1]" = "I2C_VOLTAGE_3V3"
+	# Configure I2C1 for cr50 TPM. Early init is required to set up a BAR
+	# for TPM communication before memory is up.
+	register "i2c[1]" = "{
+		.early_init = 1,
+		.speed = I2C_SPEED_FAST,
+		.speed_config[0] = {
+			.speed = I2C_SPEED_FAST,
+			.scl_lcnt = 190,
+			.scl_hcnt = 90,
+			.sda_hold = 36,
+		},
+	}"
+
+	# Camera
+	register "i2c_voltage[2]" = "I2C_VOLTAGE_1V8"
+	register "i2c[2]" = "{
+		.speed = I2C_SPEED_FAST,
+		.speed_config[0] = {
+			.speed = I2C_SPEED_FAST,
+			.scl_lcnt = 192,
+			.scl_hcnt = 90,
+			.sda_hold = 36,
+		},
+	}"
+
+	# Pen
+	register "i2c_voltage[3]" = "I2C_VOLTAGE_1V8"
+
+	# Camera
+	register "i2c_voltage[4]" = "I2C_VOLTAGE_1V8"
+	register "i2c[4]" = "{
+		.speed = I2C_SPEED_FAST,
+		.speed_config[0] = {
+			.speed = I2C_SPEED_FAST,
+			.scl_lcnt = 190,
+			.scl_hcnt = 90,
+			.sda_hold = 36,
+		},
+	}"
+
+	# Audio
+	register "i2c_voltage[5]" = "I2C_VOLTAGE_1V8"
+	register "i2c[5]" = "{
+		.speed = I2C_SPEED_FAST,
+		.speed_config[0] = {
+			.speed = I2C_SPEED_FAST,
+			.scl_lcnt = 180,
+			.scl_hcnt = 80,
+			.sda_hold = 36,
+		},
+	}"

# Use GSPI0 for cr50 TPM. Early init is required to set up a BAR for TPM
    # communication before memory is up.
    register "gspi[0]" = "{
    	 .speed_mhz = 1,
-		 .early_init = 1,
-	}"
-
-	# Configure I2C1 for cr50 TPM. Early init is required to set up a BAR
-	# for TPM communication before memory is up.
-	register "i2c[1]" = "{
    	 .early_init = 1,
    }"